The intertidal staphylinid genus Bryothinusa Casey is currently known from 28 species distributed discontinuously on widely separated sandy beaches throughout the Pacific Basin from California to Papua New Guinea and in the Red Sea and adjacent Northeast Africa. Most species are found in the intertidal zone of ocean beaches where they occur on sand, under stones on sand, burrowed in sand, or among rocks and sand. This talk will discuss the phylogenetic placement of Bryothinusa, evolution of the intertidal habitat, and possible mechanisms for producing the remarkable discontinuous distribution of the species within the Pacific Basin.